Causes Week 2020: Recording frog calls for citizen science

Causes Week runs this year from Dec 20 to 25. It shines a light on various individuals and groups, and shows how they are making a difference through their chosen causes within the community.

The Inger's Dwarf Toadlet is among the rare species captured in the recordings.
The Inger's Dwarf Toadlet is among the rare species captured in the recordings.PHOTO: LAW INGG THONG

SINGAPORE - Listen out for a chorus of frog calls after dusk.

The Herpetological Society of Singapore, which studies reptiles and amphibians, has invited the public to submit their own recordings of frog calls to help it better understand the distributions of frogs around the island.

Frogs are known to be vocal creatures, and each species has its own distinct types of alarm, mating and other calls.

They are also especially active at night and during the monsoon period as they typically breed in water bodies.

Common frog species which thrive in urban areas include the Asian toad, the dark-sided chorus frog, and the banded bullfrog. Toads belong to the frog group.

Mr Sankar Ananthanarayanan, co-founder of the Herpetological Society of Singapore, said the initiative was piloted in the hope of making people more aware of the life around them.

Over 30 recordings have been contributed since the collection began in September.

These will be analysed by the society's volunteers, and the contributors will be informed about which species they had identified.

"Understanding the bio-acoustics of the frogs is very useful as it allows us to identify the frog species in various areas, which may not be as easily detected visually.

"Having a comprehensive library can help to improve biodiversity assessments around the island," said Mr Sankar.

"Ideally, this would give us a sense of the different frog species populating the island," he added.

The recordings collected by the public can also provide scientists with information such as the time and location of the frog calls, as well as to corroborate existing data on the presence of species.

A frog call library was established by the society over a year ago, with 31 different calls from 27 different species on record so far.


Mr Sankar Ananthanarayanan said the initiative was piloted in the hope of making people more aware of the life around them. PHOTO: LAW INGG THONG

These include rarer species, and those which were part of the National Parks Board Species Recovery Programme, such as the cinnamon bush, which is only found in the Bukit Timah and Central Catchment nature reserves.

Other rare species which were captured in the recordings included the Malayan horned frog, which has a distinctive, metallic honk, and the Inger's dwarf toadlet, which lay eggs in tree holes.

"With this database of frog calls, and the contributions from the public, we hope to familiarise people with the amphibian soundscape, and identify potentially new and unrecorded species if we're lucky," said Mr Sankar.

Those who wish to submit frog recordings can do so here.